A. estimate the number of stars in the milky way as follows. first, count the number of stars within 12 light-years of the sun (32 stars). assuming that the milky way's disk is 100,000 light years across and 1,000 i thick, it's volume is about 1 billion times the volume of the region of your star count. you should therefore multiply your count by 1 billion to get an estimate of the total number of stars in the milky way.
b. your estimate from part a is based on the number of stars near the sun. compare it to the value given in this chapter (100 billion stars) and determine whether your estimate is an underestimate or an overestimate of the total number of stars in the milky way. write down a list of possible reasons why your technique gave you an under/overestimate.